As used herein the term “monomodal” refers to an industrial feedstock that contains substantially one size of particle, whereas a “bimodal” feedstock contains two sizes of particles as characterized by exhibiting a continuous probability distribution having two different modes (that is, two relatively distinct peaks identifiable by size screening). “Multimodal” indicates exhibiting a multiplicity (more than two) of such sizes or peaks.
It is well known in the art that bimodal and multimodal mixtures of particles may have certain useful industrial properties. Representative examples follow.
U.S. Pat. No. 8,177,867 discloses coal-in-water slurries having bimodal and multimodal particle size distributions.
U.S. Pat. No. 6,729,068 (Dooley et al.) discloses an engineered wood-based mulch product composed of a bimodal or multimodal blend of geometrically regular wood elements.
U.S. Pat. No. 4,589,357 discloses a bimodal biomass fuel source made from hog fuel that is capable of self-sustaining combustion in an air suspension fired burner.
Japanese Patent Publication No. 62030190 discloses a concentrated coal-water slurry having a bimodal particle diameter distribution.
International Publication No. WO 99/02766 discloses fiber matting having a bimodal fiber length distribution intended for the smooth surface coating of plywood boards.
U.S. Pat. No. 6,422,494 discloses a method of increasing the bulk density of mineral materials by sizing such materials into selective bimodal and multimodal size distributions.
Such prior art techniques often involve screening comminuted materials and combining particular size fractions into bimodal or multimodal mixtures.